1. Field
Embodiments of the present disclosure relate to a method of manufacturing a piston of a pump for brake system and a pump for brake system including the piston manufactured using the method, and more particularly, to a method of manufacturing a piston of a pump for brake system to achieve a reduction in manufacturing costs and improvement of productivity and a pump for brake system including the piston manufactured using the method.
2. Description of the Related Art
In general, an anti-lock braking system (ABS), electric stability control (ESC), electro-hydraulic brake (EMB), or the like is installed at a brake system of a vehicle. The brake system controls a braking hydraulic pressure of the vehicle to acquire driving stability of the vehicle.
The brake system is equipped with a pump to control a hydraulic pressure transmitted to wheel cylinders of the brake.
Such a brake system includes a plurality of solenoid valves, low-pressure and high-pressure accumulators to temporarily store oil discharged from a hydraulic brake, a motor and a pump to pump the oil temporarily stored in the low-pressure accumulator, and an electronic control unit (ECU) to control the operation of the solenoid valves and the motor. All of these elements are installed in a modulator block made of aluminum.
Among these elements, examples of the pump that controls the hydraulic pressure transmitted to wheel cylinders of the brake are disclosed in Korean Patent No. 10-0538512 and Korean Patent Application Publication No, 20-2011-0124602. Referring to these documents, a pump includes a piston configured to receive oil through a suction port and press the oil contained in a pressure chamber while moving forward and backward by an eccentric spindle of a motor and a piston spring configured to reciprocating the piston together with the eccentric spindle by pushing the piston toward to the eccentric spindle of the motor. The pump transmits oil toward a wheel cylinder or master cylinder of the brake by forcedly pumping oil from the low-pressure accumulator or the master cylinder to the high-pressure accumulator. In this case, the piston is generally manufactured by a forging process and has an inlet path formed by a cutting process to communicate with a suction port.
However, the method of forming the inlet path by the cutting process in the piston fabricated by the forging process may increase manufacturing costs and decrease production efficiency due to a long processing time.